This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Carbon nanotubes (CNTs) have shown an extraordinary potential for bionanoengineering applications. A promising application involves SWNT-based optical biosensors. Compared to conventional optical biosensors, carbon nanotubes have a great advantage in that they fluoresce at near-infrared wavelengths, where human tissues and biological fluids are nearly transparent. Design of SWNT based sensors requires an adequate description of the interactions between nanotubes and their biological environment.